An 18-37 record before a mid-season firing in 2008. No playoff berths for a franchise used to winning championships. A parade of offensive coordinators unable to develop Alex Smith at quarterback.

Yet to call Nolan’s run in San Francisco a complete failure would clearly miss the point. He took over a franchise decimated under the leadership of former general manager Terry Donahue and coach Dennis Erickson and began acquiring the pieces that Jim Harbaugh later used to make back-to-back runs to the NFC championship game.

Nolan, now the defensive coordinator in Atlanta, gets the chance to see the results of some of his work when the Falcons (14-3) host the 49ers (12-4-1) on Sunday with a trip to the Super Bowl on the line.

“There’s a lot of players still playing there that we added, that I’ll see. I look forward to seeing them before the game. I’m glad they’ve done well. Not only for those players, but for the organization,” Nolan said. “I put a lot of time and effort into that. So, in a strange way, it’s a little rewarding that some of those guys are going so well.”

San Francisco owner Jed York said he gives Nolan “a lot of credit for helping set the foundation for this current 49ers team.

“It’s never easy to let somebody go that you have so much respect for, and you wish things had worked out differently for Mike. … He is a very classy man and he’s a heck of a football coach,” York said. “He’s not the person that I want to see with the 49ers looking across the field knowing he is coordinating the defense of our opponent. That’s not a good thing for me to see because he is very, very good.”

Ten of the current 49ers were acquired during Nolan’s regime, including first-team All-Pros linebacker Patrick Willis and safety Dashon Goldson, second-teamers defensive tackle Justin Smith and left tackle Joe Staley and key contributors like running back Frank Gore, tight ends Vernon Davis and Delanie Walker, defensive lineman Ray McDonald and cornerback Tarell Brown.

That helped transform the organization from a laughingstock that went 2-14 in 2004 in the final season under Erickson into a respectable one that still fell short of the playoffs.

“He turned us around,” said punter Andy Lee, one of 13 players left from when Nolan coached. “When he first got here we were the worst team in the NFL. Then we slowly started this climb from being the worst team in the NFL to a mediocre, possible playoff team. He did a good job. I really don’t have anything negative to say about him. He definitely was part of the turnover part of this organization.”

But the talent Nolan acquired and the work ethic he instilled in the locker room failed to lead to success on the field. The Niners went 4-12, 7-9 and 5-11 in his three full seasons at the helm. He was fired with a 2-5 record midway through the 2008 season and has spent the past few years as a successful defensive coordinator.

After 2½ more years of mediocrity under Mike Singletary, the Niners have turned into a winner the past two seasons under coach Jim Harbaugh. San Francisco has won back-to-back NFC West titles and is in the NFC title game for the second straight season where the 49ers will face Nolan and the Falcons on Sunday.

“Nolan did some good things when he was here, definitely,” said Goldson, a fourth-round draft pick in 2007. “But it’s just a different feeling around here lately. It’s kind of hard to go back to where we were because we’ve been dealing with a lot of success lately. It’s just different.”

Nolan’s run was not without its personnel missteps, most notably the first major decision he made. With the top pick in the 2005 draft, Nolan selected Alex Smith instead of local favorite Aaron Rodgers, a decision that set the franchise back.

With a different offensive coordinator each season, Smith struggled to become a consistent NFL quarterback. Then there was a notable feud with Nolan when he tried to come back from a shoulder injury in his third season.

Smith lacked arm strength and later needed two operations, but Nolan at the time said there was nothing wrong with Smith’s shoulder and the issue was confidence. The two have long since moved past that episode and have respect for each other years later.

“I felt like I grew up and learned a lot from that entire situation,” Smith said. “We got along really well after that. I saw my fault in it. We definitely moved on. No hard feelings for sure at this point at all. I look back at that as what could I have done differently as a young player in this league. You learn from it. No resentment at all.”

Smith finally emerged last year in his first season under Harbaugh, helping lead the Niners to the NFC title game, where they lost 20-17 in overtime to the New York Giants.

Smith lost his job midway through this season to Colin Kaepernick, who has transformed the San Francisco offense with a running threat out of the pistol formation.

It provides a stiff test for Nolan’s new defense, but one the Niners are sure he will be up to.

“Absolutely,” York said. “He’s one of the brightest defensive minds in the league and I know what he brings to the table. He knows our team fairly well. It’s definitely going to give them an advantage.”